Journalist Peter Greste's parents 'rocked' by courtroom cage images

The parents of jailed Australian journalist Peter Greste say they are haunted by images of him in a courtroom cage, as a spokesman for Tony Abbott said the Prime Minister was ''deeply concerned'' about the plight of Greste, who is on trial in Egypt.

Greste faces up to seven years in prison, accused of backing the blacklisted Muslim Brotherhood and broadcasting ''misleading'' news on the political situation in Egypt. At the latest hearing in Cairo on Wednesday, Greste appeared in a cage dock, with five other defendants, wearing a white prison uniform.

His parents, Juris and Lois Greste, said that while the public support for their son had lifted their spirits, they were horrified by the images of his court appearance. ''It certainly shocked me,'' Juris Greste said in Brisbane. ''It absolutely rocked me to see him in the cage.''

Mr Greste also described the harsh conditions of his son's prison cell, which he shares with two other reporters for 23 hours a day.

Australian journalist Peter Greste, third from right, of Al-Jazeera and his colleagues inside the defendants' cage during their trial in Cairo. Photo: AFP

During the court appearance, the Al-Jazeera reporter called for Mr Abbott to speak out against his detention. Mr Abbott's spokesman said on Thursday: ''We strongly support a free media and the Australian government is deeply concerned about the charges that have been laid against Mr Peter Greste, and the fact that he is currently subject to criminal proceedings in Egypt.''

The spokesman said the Australian government had made several representations in support of his release. ''The Foreign Minister, Julie Bishop, has personally raised concerns about Mr Greste's arrest with the Egyptian government and authorities and we will continue to make representations on behalf of Mr Greste to secure his release.''

The Australian Greens say Mr Abbott owes it to press freedom to call on Egypt to release Mr Greste. ''Where are you, Tony Abbott, when an Australian citizen needs you?'' Greens leader Christine Milne said.